Kang arrived in Washington earlier in the day, accompanying President Moon Jae-in on his first official visit to the US for summit talks with President Donald Trump.

North Korea is expected to be one of the top issues for Moon's meetings with Trump set for Thursday and Friday, with a focus on how to reconcile Trump's policy of "maximum pressure" on the North with Moon's hopes to foster peace through exchanges and cooperation with the isolated neighbor.

During Thursday's talks, the two top diplomats agreed to flesh out joint strategies for resolving the North Korean nuclear issue through close cooperation while sticking firmly to the shared goal of the North's denuclearization, the South's Foreign Ministry said in a statement.

In particular, Tillerson expressed hope that the Korea-US alliance will play a crucial role in resolving the nuclear standoff, the statement said.

Tillerson and Kang also agreed to put in their best diplomatic efforts to make the upcoming summit between Moon and Trump a success while sharing an understanding that the meeting is highly symbolic itself as the first meeting since the two governments came into office, the statement said.

Kang expressed condolences over the death of American college student Otto Warmbier and said the South will work closely together with the US to help improve the North's human rights situation, the statement said. (Yonhap)